Question

Would you please help/check my answers on these probability questions because I cannot come up with what the answer book says.

A group of baseball fans at a sports bar in Illinois were asked about which professional baseball team they root for during baseball season. Use the results in the table to answer each question.

Team Number of Fans

Cubs 14
Cardinals 42
White Sox 25

a. What is the probability that a randomly selected fan is not a Cubs fan?

I said .83 because non-cubs fans are 42+25=67/81 = .83.

The answer book says .74

b. Suppose a new fan walked into the room and didn't really like baseball but wanted to play along, so she agreed to randomly select one of the three teams. What is the probability that she is a Cardinals fan?

I said .33 because she has a chance to pick Cardinals out of the three teams, 1/3 = .33

Agrees with answer book.

c. If one fan is chosen randomly, what is the probability that he or she roots for the White Sox?

I said .31 because 25/81 = .81, however, the answer book says .22 and I can't figure out how they got that.

Thank you so much for checking.

Answer 1

I completely agree with you. My only thought is that there are typos in the book. Your typo:

25/81 ≠ .81

Answer 2

Could someone else please look at this? I did not say that 25/81 was .81 and I'd also like to check my other answers. Thanks!